Pipe construction

ABSTRACT

A tensile stress resistant pipe connection comprising two male pipes and a sleeve with two conically tapering recesses, sealing means at the ends of the sleeve and coupling means situated in said recess, the free end of one male pipe in the recesses being provided with left hand screw thread, a free end of the other one with right hand screw thread of about the same pitch.

United States Patent- Wentz 285/175 Zon [451 Sept. 19,1972

[541 PIPE CONSTRUCTION 3,494,639 2/1970 Smith ..2ss/344x 2,848,1358/1958 Richard et a1. ..285/318 X [72] Invent 33;? Zwdle 701,020 5/1902-Diescher ..285/3l8 x 1,119,752 12/1914 Goethner et a1. ..285/l75 X 73Assi nee: Industriele O dernemin W 1 8 NM Zwone, FOREIGN PATENTS ORAPPLICATIONS I 650,640 7/1964 Belgium ..285/l04 [22] 1970 605,006 7/1948Great Britain ..285/1l1 pp 84,417 108,269 1/1966 Norway ..28S/113741,206 11/1955 Great Britain ..285/1 13 [52] U.S. Cl. ..285/l75,285/255, 22885532619, Primary Examiner Thomas E Callaghan 7 51 Int. Cl...Fl61 21/08 Nines [58] Field of Search ..285/113, 104, 344, 175, 318,57 AB TRACT 285/321, 339, 323,111, 255,369 1 S v I A tensile stressresistant p1pe connection comprising 5 mc two male pipes and a sleevewithtwo conically taper- Ing recesses, sealing means at the ends of thesleeve UNITED STATES PATENTS "andcoupling means situated in said recess,the free ;end of one male pipe in the recesses being provided giz gi' 2g i with left hand screw thread, a free end of the other 2 449 2959/1948 $33,22 ne with right hand screw thread of about the same 7 a a aa a a a a a a a a a a a a. t h. 3,462,175 8/1969 J0hnson....",.'..'"285/113 x P I 581,050 4/1897 8 Claims, 1 Drawing Figure PATENTEDSEP 19I972 loluumr In I INVENTOR (ORA/5L Vn/v Z 0 W ATTORNEY PIPE CONSTRUCTIONTensile stress resistant pipe connectionspwhereby from the -outer sideand through an aperture in the female pipe apart rod-shaped material,e.g. plastic rod.

or flexible metal band, is inserted into a recess in the female part andinto a' recess opposite thereto in the male pipe part, are commonlyknown. These connections have the drawback that in order to obtain thetensile stress resistant connection it is necessary to weaken the wallof the male pipe part owing to the provision of a groove foraccommodating the coupling means.

-It is now an object of the invention to provide a pipe connection ofthe afore mentioned type in which the difficulties referred to above areobviated and a connection is obtained which at all times is absolutelytensile stress resistant without the implication of inserting couplingmeans from the outside and providing a groove in the male pipe part.

This object is attained according to the invention in the way that in apipe connection comprising a female pipe part and a male pipe part,sealing means situated between the female and the male part, andcoupling means for connecting in a tensile'stress resistant way saidmale and female pipe parts in the inner side of the female pipe part arecess is provided with such a shape and dimensions that the end of themale pipe part can he slid past the coupling means accommodated in thisrecess,- while on the other hand the surface of the coupling meanscooperates in such a way with the outer wall of the male pipe part, whenthe male pipe part and the' female pipe part are again moved apart, thatas a consequence the coupling means are taken along with the male pipepart and clamped between the outer side of the male pipe part and thewall of the recess whilst forming a tensile stress resistant connection.

The coupling means consist advantageously of a spiral spring or aconically split ring, while one or both surfaces thereof that cooperatewith the pipe parts are provided with ribs, screw thread or pin shapedprojections. 7 j

Preferablyat least one and efficiently the two walls of the couplingmeans cooperating-with the walls of the pipe parts consist of a materialof an equal hardness as or harder than the material of the wall of thepipe parts jections or is profiled in an other way. If desired alsoapolyvinylchloride ring provided with a surface layer of hardpolyvinylchloride may be used. Y

By employing such deformable coupling means with a surface harder thanthe pipe parts to be connected the hard profile will penetrate into thethermoplastic material and in this way an absolutely dependable stressresistant connection will be achieved.

On using thermoplastic pipe parts and e.g. a coupling meansconsisting ofa steel ring, it is advisable, in order to prevent deformations in thewall of the male pipe part, owing to the pressure exerted by thecoupling means, to provide a steel sleeve therein.

, the recess 4 taperingin the direction of the free end 6 In order topromote a cooperation between the coupling means and the male pipe partthe outer side of the end part of the male. pipepart may also beprofiled, e.g. be threaded. Hereby even with smooth coupling means it ispossible to achieve that e.g. couplingrneans gripping the male pipe partare taken along.

The invention will now be clarified with reference to the drawing inwhich an embodiment is represented,

the part A of the FIGURE showing a pipe'connection according totheinvention with a conical ring as a coupling means and the part Bshowing a circular wound spring as a coupling means. i V In thesefigures a pipe connection is represented comprising a female pipepart inthe shape of a sliding sleeve 1 of polyethylene with two female pipeparts 2 and 2' of similar polyethylene. In the female pipe parts 2 and 2is amale pipe part 3, 3",- respectively. lnthe parts 2 and 2' of thesliding sleeve are recesses 4, 4' for accommodating the coupling means5, 5', respectively. Instead of polyethylene other thermoplastics suchas polypropylene or pvc may be used.

The coupling means 5 of a conically splitring of polyethylene (of thesame hardness as or harder than the polyethyleneofthe-pipes and/orsleeve) are introduced from the free end 6 of the female pipe part 2into a conically tapering recess 4, whereupon the male pipe part 3 isinserted. The split ring 5 has an inner diameter such that the end 7 ofthe male pipe part 3 can pass .while the ring 5 by its end wall 8 ispressed against the end wall 9 of the recess 4. Since on the other handthe split ring is formed in such a way that same grips the outer wall 10of the. male pipe part 3,,the ring 5 is taken along when the male pipepart 3 is retracted from the female pipe part 2 and becomes wedgedbetween the outer wall 10 of the male pipe part 3 and the wall 11 of ofthe female pipe part. 7 v

The surface of the outer wall 10 of the male pipe part 3 isadvantageously provided with a screw thread or ribs 14.

The surface 12 of the ring 5, which cooperates with the wall of therecess 4 is conveniently profiled e.g. in the shape of ribs andpreferably of screw thread. Also the surface 13 is preferably threaded.1

On retracting the male pipe part from the female pipe part the ribs orthe screw thread 14 will contribute to the formation of a proper tensilestress resistant connection and also enable the ring 5 to be taken with.Furthermore sealing means 15, 16, respectively are provided which areaccommodated in a recess 17, 18, respectively of the female pipe part.These sealing means are indispensable when the free end of outer surface13 of pipe 3 and the corresponding surface of pipe 3' are provided withscrew thread or other profilation allowing liquid to escape from.theinner sideto the outer side. i

A particular advantage of this constructionas shown in the left part ofthe figureis that the coupling means are situated in a region where theinner pressure on pipe 3 and the outer pressure on pipe 3 in recess 4are substantially equal. This construction prevents any damage to'thepipe, which cannot be excluded when there is any pressure differencebetween the inner and outer side of the pipe in the region ofcooperation between coupling means 5 and pipe 3.

I connection at least the surface of the coupling means 5,

'. that is to say ring, spiral spring and the like, is preferably madeof-a material harder than the surfaces of the pipe parts to beconnected.

'The' split ring '5 can Ye.g. consist of hard polyvi nylchloride whenthe polyethylene pipes are connected in a tensile stress resistant way.

. If desired a steel sleeve 22 may be provided in the ends 7 and 7' ofthe male pipe parts 3 and 3'.

In order to avoid symptons of fracture the corner 21 of the recess 4 andthe corner 21' of the recess 4 are rounded. The end walls 9 and 9'should be constructed in such a way than on moving inwards the male pipepart the coupling means 5, 5' are retained with respect to the male pipepart 3,3.

. ,The sliding sleeve represented in the drawing is provided with anabutment edge, but this is not necessary. Without an abutment edge it ispossible, in case of a male pipe part on which the profiled portion endsat some distance from the end (7,7') that the pipe part 3 after havingbecome wedged is slid back again and to grip, by means ofa tool, fromthe end of part 2' of the sliding sleeve the ring-shaped coupling meansand subsequently pull'outwards the pipe part 3. After the pipe part3"has been mounted this is obviously no longer possible.

It is evident that the split solid ring 5 may also consist of metalwhich in-particular cases is preferably with thermoplastic pipes. It isalso possible to use eg a plastic ring consisting of hardpolyvinylchloride the surfaces of which consist of a hard metal, thesesurfaces being e.g. profiled, whereby also the desired tensile stressresistant connection is obtained.

In order to remove a pipe 3 or 3' from the inner side of the sleeve 1,also connected with a pipe 3' and coupling means 5' having a similarshape as coupling means 5, it is recommended to provide the completefree end of the outer surface 13 of pipe 3 with right handed screwthread and the complete free end of the outer surface of pipe 3' withleft handed screw thread of the same pitch or vice versa. It will beobvious that in those cases the surfaces of the coupling meanscooperating with the outer surfaces of pipes 3 and 3' have screw threadadapted to the screw thread of outer surfaces of pipe 3 and 3.

In this way the sleeve 1 can be screwed to the left or to the rightdepending on the screw thread until the ends 7 or 7 of pipes 3 or 3' arecompletely free from the sleeve 1 The pipe 3 or 3' can now be removedand afterwards the connection will be restored by screwing sleeve 1 inthe direction of pipe 3 or 3'. It will be obvious that in thisembodiment the inner collar of sleeve 1 between 7 and 7 must be absent.

What I claim is; g

l; A pipe connection comprising a female pipe part and a male pipe part,sealing means situated and between and sealingly engaging the female andmale parts, annular coupling means of at least the same hardness as thepipe parts for connecting in a tensile stress resistant way the male andfemale parts, said female part being provided on the inner side thereofwith a single annular recess conically tapering inwardly in the thefemale and direction of the free'end of thefemale pipe part and of ashape and dimensionssuchthat the end of the-male pipe part can be slidpast the coupling-means accommodated in said recess, thesurface of thecoupling means cooperating in such a way with the outer. surface of thewall of the male pipe part, whenvthe male part and the female part moveaway from each other, that the coupling means are moved thereby with themale part and become wedged between the outer side of the male pipe partand the wall of the recess while forming a tensile stress resistantconnection, the free end of a male pipe part being provided with a screwthread which cooperates with a similar screw thread on the cooperatingsurface of the coupling means, anda sleeve provided in the inner side ofmale part opposite the coupling means in order to prevent deformation ofthe male pipe part.

2. A pipe connection according to claim 1, wherein the coupling meansconsist of a'closed spiral spring and said sealing means areaccommodated between the end of the female pipe part and said malepipepart.

3. A pipe connection according to-claim 1 comprising one female pipepart and two male pipe parts wherein the free end of the outer surfaceof a first male pipe part is provided with a right hand screw thread andthe free end of the outer surface of the second male pipe part with aleft 'hand screw thread of about a similar pitch, said female pipe partbeing provided with a second annular recess, and second annular couplingmeans are positioned in said second recess and cooperate with the lefthand screw thread of the second male pipe part.

4. A pipe connection according to claim 3, wherein male pipe partsconsist of thermoplastic material.

5. A pipe connection according to claim 4 wherein said thermoplasticmaterial is polyethylene.

6. A pipe connection according to claim 4 wherein said thermoplasticmaterial is polypropylene- 7. A pipe connection according to claim 1wherein said sleeve is metal.

8. A pipe connection according to-claim 1 wherein the coupling meansconsist of a ring which is longitudinally split and conicallyconstructed and said sealing means are accommodated between the end ofthe female pipe part and said male pipe part.

* s a l

1. A pipe connection comprising a female pipe part and a male pipe part,sealing means situated and between and sealingly engaging the female andmale parts, annular coupling means of at least the same hardness as thepipe parts for connecting in a tensile stress resistant way the male andfemale parts, said female part being provided on the inner side thereofwith a single annular recess conically tapering inwardly in thedirection of the free end of the female pipe part and of a shape anddimensions such that the end of the male pipe part can be slid past thecoupling means accommodated in said recess, the surface of the couplingmeans cooperating in such a way with the outer surface of the wall ofthe male pipe part, when the male part and the female part move awayfrom each other, that the coupling means are moved thereby with the malepart and become wedged between the outer side of the male pipe part andthe wall of the recess while forming a tensile stress resistantconnection, the free end of a male pipe part being provided with a screwthread which cooperates with a similar screw thread on the cooperatingsurface of the coupling means, and a sleeve provided in the inner sideof male part opposite the coupling means in order to prevent deformationof the male pipe part.
 2. A pipe connection according to claim 1,wherein the coupling means consist of a closed spiral spring and saidsealing means are accommodated between the end of the female pipe partand said male pipe part.
 3. A pipe connection according to claim 1comprising one female pipe part and two male pipe parts wherein the freeend of the outer surface of a first male pipe part is provided with aright hand screw thread and the free end of the outer surface of thesecond male pipe part with a left hand screw thread of about a similarpitch, said female pipe part being provided with a second annularrecess, and second annular coupling means are positioned in said secondrecess and cooperate with the left hand screw thread of the second malepipe part.
 4. A pipe connection according to claim 3, wherein the femaleand male pipe parts consist of thermoplastic material.
 5. A pipeconnection according to claim 4 wherein said thermoplastic material ispolyethylene.
 6. A pipe connection according to claim 4 wherein saidthermoplastic material is polypropylene.
 7. A pipe connection accordingto claim 1 wherein said sleeve is metal.
 8. A pipe connection accordingto claim 1 wherein the coupling means consist of a ring which islongitudinally split and conically constructed and said sealing meansare accommodated between the end of the female pipe part and said malepipe part.